This operand will make use of any indexes that may be available on the
geometries. It is different from other operators that use spatial indexes in that the spatial index is only used when the operator
is in the ORDER BY clause.

Index only kicks in if one of the geometries is a constant e.g. ORDER BY
(ST_GeomFromText('POINT(1 2)') <<#>> geom) instead of g1.geom
<<#>>.